Floors & Ceilings

Leca® insulation and drainage of floors

Mortars based on lime and gypsum have a long tradition of use in floors, either as lime concrete or combined with bricks and stones. These floors can be insulated effectively with the use of modern, yet all natural, materials.

The use of a floor

Hard use will always affect a floor, and the decaying processes normally found in mortars for pointing, rendering and plastering will also be present in such floors. Damage to be dealt with includes moisture penetration, abrasion and impact, a lack of supporting structure as well as inappropriate repair and maintenance. Water penetration and a lack of insulation are also issues to be dealt with when the use and inhabitants of the building are changing.

Insulated Leca® floors

Floor Leca Insulation

2000 years ago, Vitruvius described the use of insulated structures in the floor to reduce heat loss from the building. He described the use of charcoal between the hard core and the lime concrete, but with specifications that differ little from the method used today to construct lightweight, insulated floors. In addition to insulating the floor and providing a solid base for further build-up of the floor, the lack of capillaries prevents uptake of groundwater when the floor is directly on compacted subsoil. In floor foundations, the use of lightweight Leca® can replace sand, as is often found in older floors, to reduce sound penetration and increase insulation. The build-up of the floor can then be traditional with lime concrete and finished off with lime-ash mortars / lime concrete, bricks, tiles, etc. Bricks are set in lime-based mortar to make sure the movements are cohesive with the movements in the lime concrete. Old mosaic and tile floors need to be conserved by a specialised curator. In many cases, the old mosaic floors are still in situ in their original lime bedding.